Duality of Love

The nature of love and affection is something that has always struck me as being contradictory. It seems that without it, we feel incomplete and isolated. We have the overwhelming desire to fill the void.
Once we attain it though, we become so frightened of losing the sensation that we no longer feel it. Instead we are too busy trying to maintain it to appreciate it.
We only seem to catch glimpses of it, and it is during those moments that we really understand its significance on who we are. I feel like recently I've caught sight of it a lot more, and as a result I am more scared than ever that I could damage what I have. I have this overwhelming need and desire for someone, yet the only reason I have it is because I am scared of what I am without that need.
It feels like love is basically us using someone else as justification for an emotion. Without them, we feel incomplete. With them, we feel scared of returning to incompleteness.
That we require another individual to resolve our own insecurities is more a reflection on ourselves as individuals than it is on us as social beings. Nearly all other emotions are able to be generated and resolved internally and without the necessity of a third party (although this often does help). Love is different though, and perhaps why it continues to fixate all of mankind.
I know I am in love, but exactly what that means will perhaps be forever a mystery to me.